namespace NetinaShop.Api.WebFramework.MiddleWares;

public static class ExceptionHandlerMiddlewareExtensions
{
    public static IApplicationBuilder UseExceptionHandlerMiddleware(this IApplicationBuilder applicationBuilder)
    {
        return applicationBuilder.UseMiddleware<ExceptionHandlerMiddleware>();
    }
}

public class ExceptionHandlerMiddleware
{
    private readonly IWebHostEnvironment _env;
    private readonly ILogger<ExceptionHandlerMiddleware> _logger;
    private readonly RequestDelegate _next;

    public ExceptionHandlerMiddleware(
        RequestDelegate next,
        IWebHostEnvironment env,
        ILogger<ExceptionHandlerMiddleware> logger)
    {
        _next = next;
        _env = env;
        _logger = logger;
    }

    public async Task Invoke(HttpContext context)
    {
        string message = null;
        var httpStatusCode = HttpStatusCode.InternalServerError;
        var apiStatusCode = ApiResultStatusCode.ServerError;

        try
        {
            await _next(context);
        }
        catch (BaseApiException exception)
        {
            _logger.LogError(exception, exception.Message);
            httpStatusCode = exception.HttpStatusCode;
            apiStatusCode = exception.ApiStatusCode;

            if (_env.IsDevelopment())
            {
                var dic = new Dictionary<string, string>
                {
                    ["Exception"] = exception.Message,
                    ["StackTrace"] = exception.StackTrace
                };
                if (exception.InnerException != null)
                {
                    dic.Add("InnerException.Exception", exception.InnerException.Message);
                    dic.Add("InnerException.StackTrace", exception.InnerException.StackTrace);
                }

                if (exception.AdditionalData != null)
                    dic.Add("AdditionalData", JsonConvert.SerializeObject(exception.AdditionalData));
                var contractResolver = new DefaultContractResolver
                {
                    NamingStrategy = new CamelCaseNamingStrategy()
                };

                message = JsonConvert.SerializeObject(dic, new JsonSerializerSettings
                {
                    ContractResolver = contractResolver,
                    Formatting = Formatting.Indented
                });
            }
            else
            {
                message = exception.Message;
            }
            if(exception.AdditionalData==null)
                await WriteToResponseAsync();
            else
                await WriteToResponseWithObjectAsync(exception.AdditionalData);
        }
        catch (SecurityTokenExpiredException exception)
        {
            _logger.LogError(exception, exception.Message);
            SetUnAuthorizeResponse(exception);
            await WriteToResponseAsync();
        }
        catch (UnauthorizedAccessException exception)
        {
            _logger.LogError(exception, exception.Message);
            SetUnAuthorizeResponse(exception);
            await WriteToResponseAsync();
        }

        catch (Exception exception)
        {
            _logger.LogError(exception, exception.Message);

            if (_env.IsDevelopment())
            {
                var dic = new Dictionary<string, string>
                {
                    ["Exception"] = exception.Message,
                    ["InnerException"] = exception.InnerException?.Message,
                    ["StackTrace"] = exception.StackTrace
                };
                message = JsonConvert.SerializeObject(dic);
            }

            message = exception.Message;
            await WriteToResponseAsync();
        }

        async Task WriteToResponseAsync()
        {
            if (context.Response.HasStarted)
                throw new InvalidOperationException("The response has already started, the http status code middleware will not be executed.");

            var result = new ApiResult(false, apiStatusCode, message);

            var contractResolver = new DefaultContractResolver
            {
                NamingStrategy = new CamelCaseNamingStrategy()
            };

            var json = JsonConvert.SerializeObject(result, new JsonSerializerSettings
            {
                ContractResolver = contractResolver,
                Formatting = Formatting.Indented
            });

            context.Response.StatusCode = (int)httpStatusCode;
            context.Response.ContentType = "application/json";
            await context.Response.WriteAsync(json);
        }



        async Task WriteToResponseWithObjectAsync(object additionalData)
        {
            if (context.Response.HasStarted)
                throw new InvalidOperationException(
                    "The response has already started, the http status code middleware will not be executed.");

            var result = new ApiResult<object>(false, apiStatusCode, additionalData, message);

            var contractResolver = new DefaultContractResolver
            {
                NamingStrategy = new CamelCaseNamingStrategy()
            };

            var json = JsonConvert.SerializeObject(result, new JsonSerializerSettings
            {
                ContractResolver = contractResolver,
                Formatting = Formatting.Indented
            });

            context.Response.StatusCode = (int)httpStatusCode;
            context.Response.ContentType = "application/json";
            await context.Response.WriteAsync(json);
        }

        void SetUnAuthorizeResponse(Exception exception)
        {
            httpStatusCode = HttpStatusCode.Unauthorized;
            apiStatusCode = ApiResultStatusCode.UnAuthorized;

            if (_env.IsDevelopment())
            {
                var dic = new Dictionary<string, string>
                {
                    ["Exception"] = exception.Message,
                    ["StackTrace"] = exception.StackTrace
                };
                if (exception is SecurityTokenExpiredException tokenException)
                    dic.Add("Expires", tokenException.Expires.ToString());

                message = JsonConvert.SerializeObject(dic);
            }
        }


        JwtSecurityToken ReadJwtToken(bool fromHeader = true)
        {
            try
            {
                if (fromHeader)
                {
                    var stream = context.Request.Headers.Values.First(v => v.FirstOrDefault().Contains("Bearer"))
                        .FirstOrDefault();
                    var handler = new JwtSecurityTokenHandler();
                    var jsonToken = handler.ReadToken(stream.Split(" ").Last());
                    return jsonToken as JwtSecurityToken;
                }
                else
                {
                    string stream = context.Request.Query["access_token"];
                    ;
                    var handler = new JwtSecurityTokenHandler();
                    var jsonToken = handler.ReadToken(stream.Split(" ").Last());
                    return jsonToken as JwtSecurityToken;
                }
            }
            catch (Exception e)
            {
                throw new BaseApiException(ApiResultStatusCode.UnAuthorized, e.Message + " Jwt is wrong",
                    HttpStatusCode.Unauthorized);
            }
        }
    }
}